We can work out the first three terms of this quadratic equation with substitution. The first term of this sequence is where n=1, we can substitute 1 in for n y=1^2+2(1)-4 y=1+2-4 y=-1 We can do this for the next two terms as well y=2^2+2(2)-4 y=4+4-4 y=4 For the last term: y=3^2+2(3)-4 y=9+6-4 y=11